Down-hole pump



Oct. 22, 1957 E. R. BOWER DOWN-HOLE PUMP Filed Aug. 22, 1956 XIBLE BLADDER TUBING ANCHORAGE 3 OIL PRODUCING FORMATION I3 RE WRAPPING Inventor Edward R. Bower il Attorney United States Patent O DOWN-HOLE PUMP Edward R. Bower, Caracas, Venezuela, assignor to Esso Research and Engineering Company, a corporation of Delaware Application August 22, 1956, Serial No. 605,629

4 Claims. (Cl. 103148) The present invention is concerned with improved down-hole pump adapted for use in well boreholes. The invention is particularly concerned with a method for increasing the recovery of oil, utilizing a bladder type pump which can be activated from the surface and which will more effectively raise the oil to the surface.

In the recovery of oil from subterranean formation, particularly, from those formations which do not contain a natural driving force, it is necessary to insert pumping means into the liquid in the borehole about the producing formation. Many types of pumps have been suggested and are currently being employed. However, these pumps in most instances are of a mechanical nature and are subject to failure of metal parts due to stresses and also due to the corrosive effect of the liquids on the metal. In accordance with the present invention a new improved bladder type pump is employed which is activated from the surface by means of a torsion rod.

The improved bladder torsion type pump of the present invention may be fully understood by reference to the drawing illustrating one embodiment of the same. Referring specifically to the drawing, a casing element 1 is shown extending from the earths surface 2 into oil producing formation 3. The oil or fluid level in the bore hole extends somewhat above the oil producing formation to a height 4. In accordance with the present invention, the flexible bladder torsion type pump 5 of the present invention is positioned in the casing 1 below the height of the oil level. The pump is attached at the lower end of a pipe string 6 which is anchored against rotation by means of an anchorage assembly 7. A torsion rod 8 extends from the earths surface downwardly through the pipe string 6 and also extends through the bladder pump 5 to a header 9 comprising the lower end of the bladder pump. A top header 10 is attached to the lower end of the pipe string 6 and does not rotate. Valves 11 are positioned at the top of the bladder pump which valves open against an upward thrust and close against a downward thrust. A seal or packing 12 is provided to prevent the flow of fluid along the torsion rod 8.

The bladder pump element of the present invention is characterized by a wire wrapping 13 which is attached to the flexible material and to the lower header. The wire wrapping is characterized in that the angle of the wire from the horizontal varies as the wire approaches the top of the bladder pump. In general, it is preferred that the angle of the wire wrapping at the bottom of the bladder pump be in the range from about 25-35", preferably, about 30 and that the angle of the wire at the top of the bladder be in the range from about 40-50, preferably, in the range of about 45. The pump 8 also con- 2,810,351 Patented Oct. 22, 1957 tains valve elements 15 in the lower header which open against an upward thrust and close against a downward thrust. In operation, the wire Wrapping forms as a helix spring and will tend to expand the bladder pump.

In operation, the bladder pump is positioned below the top of the fluid level 4. The interior of the bladder being empty, the oil will exert a downward thrust on valves 11 and an upward thrust on valves 15, thereby opening the latter valves. The bladder thus will become full of liquid. The torsion rod then is rotated from the surface winding up the helix and contracting the interior of the bladder in a progressive manner from the bottom upwardly. Under a downward thrust, valves 15 will close and valves 11 will open. Liquid, therefore, will be pumped upwardly through valves '11 into the pipe string 6 and will flow to the surface in the area between the torsion rod 8 and pipe string 6. When the bladder pump is empty, the torsion rod will be unwound and valves 11 will close, while valves 15 will open. The flexible bladder will be expanded and liquid will then flow into the bladder through valves 15 and the cycle repeated.

The manner of attaching the wire to the flexible material of the pump may be varied appreciably. While the wire may be attached on the outer surface, it can be embedded in the walls of the material or even positioned on the inner surface.

What is claimed is:

1. Apparatus adapted for lifting liquid from a subterranean location in a well borehole to the surface which comprises a flexible bladder type element having an upper header element and a lower header element, adapted to be positioned in the fluid in the well borehole, a conduit element within said borehole extending from the surface to said upper header element and communicating to within said bladder element, valve means positioned in said upper header element which open under an upward thrust and close under a downward thrust, valve means positioned in said lower header element which open under an upward thrust and close under a downward thrust, a torsion rod within said conduit element extending from the surface to said lower header, a wire wrapping attached in a spiral about said bladder element, tubing anchorage preventing the rotation of said conduit element and said upper header, means for rotating said torsion rod at the surface, whereby as said torsion rod is rotated, said lower header will be rotated, thereby rotating said wire wrapping and exerting pressure on fluid within said bladder whereby said valves in said lower header close and said valves in said upper header will open and fluid will flow upwardly to the surface in the area between said torsion rod and said conduit.

2. Apparatus as defined by claim 1 wherein the lower end of said wire wrapping is attached to said lower header and the upper end of said wire wrapping is attached to said upper header.

3. Apparatus as defined by claim 2 wherein the angle of said wire wrapping from the horizontal increases as the wire wrapping goes up said bladder.

4. Apparatus as defined by claim 3 wherein said angle increases in the range from about 25 to 35 to a range from about 40 to 50.

References Cited in the file of this patent FOREIGN PATENTS 3,152 Great Britian of 1904 

